i have a little bit of a problem that i just realized was a problem yesterday at the gas station. i know that i have a 93 octane chip and need the premium fuel but ilooked at the sticker yesterday for the first time and saw that they only have 91 at the pump. i've drove all around town and 91 is the highest octane at any pump. right now i'm only running 10 lbs of boose sence i don't want to push my 150k engine any farther than i have to, so i'm not worried about detonation right now too much. i do plan on rebuilding my engine in the next few weeks and i'll probably crank the boost up to 15+, about as far as i can go with 0 knock. so would i be better off just spending the money for race fuel for my daily driver or go to an alochol injection or propane? i am at about 5,500 ft. so would that lack of o2 offset the lower octane?
91 octane on 93 chip?
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Your altitude is why you can't get the higher octane fuels. Higher altitude = lower cylinder pressure = less octane reqirement.
Adding one or two gallons of race gas to a tank of 91 should enable any 93 chip to be run at 18 psi of boost. This will add about $5.00 - $10.00 per fill-up, but depending how much you drive the car, could take a while to equal the cost of a Propane or alcohol system.
An alternative to running race gas is buying zylene or toluene and adding it to the tank a few gallons at a time. Chemical supply houses might allow a cheaper price on these per gallon than race gas.
Adding one or two gallons of race gas to a tank of 91 should enable any 93 chip to be run at 18 psi of boost. This will add about $5.00 - $10.00 per fill-up, but depending how much you drive the car, could take a while to equal the cost of a Propane or alcohol system.
An alternative to running race gas is buying zylene or toluene and adding it to the tank a few gallons at a time. Chemical supply houses might allow a cheaper price on these per gallon than race gas.
At the "local" tracks (1 and 2 hours away) the 117 octane goes for about $7.50 a gallon. Thats the same as Xylene will get you, and around here Xylene's actually more expensive. Plus with Xylene you should use something like Marvel Mystery Oil for lube (just a few shots per gallon).
ALL of which is a pain compared to getting a scantool. Find out how much boost you can run on 91 with that chip. I'm sure it's more than 10 psi but I wouldn't jump it right up to 15+ without slowly building and checking knock the whole way. A scantool will tell you how much boost to run. Then when you decide it's not enough, go with an SMC alky kit and crank it. Good luck!
PS What is the timing on your chip, do you know? I've seen quite the range on 93 chips...like 18-22 degrees.
ALL of which is a pain compared to getting a scantool. Find out how much boost you can run on 91 with that chip. I'm sure it's more than 10 psi but I wouldn't jump it right up to 15+ without slowly building and checking knock the whole way. A scantool will tell you how much boost to run. Then when you decide it's not enough, go with an SMC alky kit and crank it. Good luck!
PS What is the timing on your chip, do you know? I've seen quite the range on 93 chips...like 18-22 degrees.
the previous owner set it at 10lbs and i haven't bothered to change it. i should be getting a knock gauge soon so i can play with the boose a little but, but even if i don't have any knock i still don't want to put much extra stress on the engine, its fast enough like it is, and if a i go off and drop a rod it won't be fast at all... i'm not sure what timming the chip is, i actually emailed the previous owner yesterday to find out what the timming is
forgot to tell you that i have 150k on the engine, i know its over due for a rebuild, but money is pretty tight...
forgot to tell you that i have 150k on the engine, i know its over due for a rebuild, but money is pretty tight...
For a daily driver, I say alcohol injection hands down. You don't use it unless you get into it. I've got a single nozzle setup, low alcohol pump speed, 170k miles, and see 20 lbs all the time.
Other than 150k miles, does your engine show signs of needing rebuild? I wouldn't rebuild unless you have a problem.
Other than 150k miles, does your engine show signs of needing rebuild? I wouldn't rebuild unless you have a problem.
i'm intrested to konw why you say that? if theres a logical reason why i should let it go i would rather spend the money in bolt on goodies than new bearings and other things that don't help much. I don't want to be left stuck out somewhere with a rod sticking out the side of the block (i know thats a bit ont he extreme side) or gernade my engine. i was just figuring $150k is a lot of miles, i know the car was taken care of very well but i still don't knw what the previous owners drove it like, i'm thinking better safe than sorry. but if its not something needed i'm ok with leaving it.
would you say just get a knock gauge and go off what it says or is there some other way to determine if it needs a rebuild? it doesn't make any funny noises other than a ticking noise that i'm almost sure is just air hitting the headers which might have a crack. what should I look for?
It's really just a matter of opinion and comfort level.
1. You can rebuild it in advance to keep from being stranded or possibly inflicting more damage than necessary.
or
2. You can drive it until it shows signs of needing it (low oil pressure, rod knock). You may be surprised at how long it will last, but you may be disappointed if you have a catastrophic failure.
To me, it's not a significant difference in cost if parts are severely damaged vs. doing a standard rebuild, so I can't justify an advance rebuild, not to mention the downtime of my daily driver and a $2500 insurance policy. Also, my comfort level with a rebuild isn't as high as the original.
I don't know the history of mine 100%, but the previous owner was pretty sure it wasn't opened up. I don't have the cash to do a rebuild and I certainly don't have the cash to rebuild it the way I want, so I'm driving it till it's required. There was a recent thread about a guy that took a 200k driver to the track, ran 12's and drove it home and another about a guy with a 300k GN driver, so miles don't always mean the engine needs a rebuild.
1. You can rebuild it in advance to keep from being stranded or possibly inflicting more damage than necessary.
or
2. You can drive it until it shows signs of needing it (low oil pressure, rod knock). You may be surprised at how long it will last, but you may be disappointed if you have a catastrophic failure.
To me, it's not a significant difference in cost if parts are severely damaged vs. doing a standard rebuild, so I can't justify an advance rebuild, not to mention the downtime of my daily driver and a $2500 insurance policy. Also, my comfort level with a rebuild isn't as high as the original.
I don't know the history of mine 100%, but the previous owner was pretty sure it wasn't opened up. I don't have the cash to do a rebuild and I certainly don't have the cash to rebuild it the way I want, so I'm driving it till it's required. There was a recent thread about a guy that took a 200k driver to the track, ran 12's and drove it home and another about a guy with a 300k GN driver, so miles don't always mean the engine needs a rebuild.
Captain Mark
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Go to the nearest paint supply place and get 5 gallons of Xylene until you decide on what to do. I can get it here for $22 bucks for 5 gallons. Money well spent. Mix 1 gallon to 2 gallons of gas. Add a few cap fulls of Marvel Mystery oil with the Xylene for lube. Search this board. Lots of info on Xylene.
Rebuild?
The Buick V6 is not prone to catastrophic failure, like a rod through the block. At high power levels, with race gas and high boost, you can break a crank, though. The "weakest link" on the engine is the weak head bolt system. There are only eight head bolts, and they are small,so the first thing to go, usually, is the head gasket. The other thing to be careful of is the timing chain. The stock chain drive has plastic teeth, which sometimes strip off, and can lead to valves hitting pistons. Even that shouldn't require a rebuild, though, just some head work. Because the engine builds power a low rpm, rather than winding tight like a Chevy or a Ford, it is not as hard on internal parts. On, yeah, you probably need new valve springs, too. But not a rebuild. Get a new timing chain, new valve springs, and a scan tool, and go at it!
The Buick V6 is not prone to catastrophic failure, like a rod through the block. At high power levels, with race gas and high boost, you can break a crank, though. The "weakest link" on the engine is the weak head bolt system. There are only eight head bolts, and they are small,so the first thing to go, usually, is the head gasket. The other thing to be careful of is the timing chain. The stock chain drive has plastic teeth, which sometimes strip off, and can lead to valves hitting pistons. Even that shouldn't require a rebuild, though, just some head work. Because the engine builds power a low rpm, rather than winding tight like a Chevy or a Ford, it is not as hard on internal parts. On, yeah, you probably need new valve springs, too. But not a rebuild. Get a new timing chain, new valve springs, and a scan tool, and go at it!
from what was told the timming chain was replaced a few thousand miles ago so i'm guessing its ok. I think i'll pull the heads check the cylenders for any excessive wear and go off what i see there, as far as how much i should do. replace vlave springs and gaskets? shoudl i also pull the crank out and check the bearings there too sence its not a TON of work or woudl you say there ok if everything else checks out? i'm liking this idea of not spending money 
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Octane
Did I see your car near Brighton's McDonalds last week?
My local Colorado Springs Farm Crest store sells 93 octane. You might find one near you. I know there are some in Denver.
"Mountain States" sell gas with about 2 less octane than states with lower elevation. Non turbo cars don't even notice. Has something to do with thin air (really).
About a need for an overhaul....One of the best Buick mechanics in the country lives close to you. Call Larry STrube @ 1-303-857-9064 ....He can give you good advice on any aspect of your car. He has earned my respect and trust, and always tells the truth....even when I'm not ready for it
Good Luck
Did I see your car near Brighton's McDonalds last week?
My local Colorado Springs Farm Crest store sells 93 octane. You might find one near you. I know there are some in Denver.
"Mountain States" sell gas with about 2 less octane than states with lower elevation. Non turbo cars don't even notice. Has something to do with thin air (really).
About a need for an overhaul....One of the best Buick mechanics in the country lives close to you. Call Larry STrube @ 1-303-857-9064 ....He can give you good advice on any aspect of your car. He has earned my respect and trust, and always tells the truth....even when I'm not ready for it
Good Luck
- Joined
- May 27, 2001
- Messages
- 9,487
Re: Rebuild?
/me looks at the rod hanging out of the Project X block.
Once you secure the crank in the block with caps or a girdle, you'll break a rod before you break a crank.
/me looks at the rod hanging out of the Project X block.
Once you secure the crank in the block with caps or a girdle, you'll break a rod before you break a crank.
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No, I'm not saying that at all.
If it were my car and everything SEEMED okay, like it's not using oil or smoking on startup then I'd open it up, change the timing chain to something more reliable, maybe put a thrust plate on the oil pump and put some valve springs on it and button it back up.
I know lots of people who have gone well over 200k on these engines without doing any more than what I listed above.
Let's be realistic. With the mods you have, you aren't going to put a rod through the block or break a crank.
If it were my car and everything SEEMED okay, like it's not using oil or smoking on startup then I'd open it up, change the timing chain to something more reliable, maybe put a thrust plate on the oil pump and put some valve springs on it and button it back up.
I know lots of people who have gone well over 200k on these engines without doing any more than what I listed above.
Let's be realistic. With the mods you have, you aren't going to put a rod through the block or break a crank.
Matt Weiser
It's an F.U.V.
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- Dec 17, 2001
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Do a compression check and/or a leakdown test to find out the condition of your engine. If these tests look OK and you're not seeing any blue smoke and you're not eating oil or coolant, leave it. Replace the valve springs and start learning how to tune the car and then start playing with bolt-ons.
I built my wagon using a 140k-mile drivetrain out of an '86 T-type. Compression was good so I replaced timing chain, valve springs and a whole bunch of leaky/broken external stuff and the thing runs like a tank. These motors are pretty stout. I'm keeping boost low for now while I learn how to tune the thing and make it faster.
That said, I have a Joe Lubrant 93 chip that I bought used and I'm planning to install. I asked Joe whether I could run the chip on the 91 octane Calif. gas I get here, and he said it's doable if I keep the boost down. The chip has 20* of timing, which I've since learned is less than a stock chip. I've also learned that the high timing in a stock chip is a big reason for the knock I'm getting on 91 octane. So we'll see how it works.
I built my wagon using a 140k-mile drivetrain out of an '86 T-type. Compression was good so I replaced timing chain, valve springs and a whole bunch of leaky/broken external stuff and the thing runs like a tank. These motors are pretty stout. I'm keeping boost low for now while I learn how to tune the thing and make it faster.
That said, I have a Joe Lubrant 93 chip that I bought used and I'm planning to install. I asked Joe whether I could run the chip on the 91 octane Calif. gas I get here, and he said it's doable if I keep the boost down. The chip has 20* of timing, which I've since learned is less than a stock chip. I've also learned that the high timing in a stock chip is a big reason for the knock I'm getting on 91 octane. So we'll see how it works.
Re: Octane
srry, i must have looked over this post before. you probly did, its a dark green t-type with the ugly vinal roof. i work at arbys right across the street (same side of the highway) actually i think one of the days i went over to mcdonalds to get an icecream, so you might have seen me.
srry, i must have looked over this post before. you probly did, its a dark green t-type with the ugly vinal roof. i work at arbys right across the street (same side of the highway) actually i think one of the days i went over to mcdonalds to get an icecream, so you might have seen me.
Was doing a search for boost related probs and ran into this thread.
You can buy 93.5 octane gas at the corner station on Parker road and Quincy Ave. About 5 Miles south of 225.
I know it's a bit of a drive for you,...but if you are going to fill it up it might be worth it.
Awesome price to,... appx 1.69 last time I went through.
You can buy 93.5 octane gas at the corner station on Parker road and Quincy Ave. About 5 Miles south of 225.
I know it's a bit of a drive for you,...but if you are going to fill it up it might be worth it.
Awesome price to,... appx 1.69 last time I went through.
93.5 huh? i know up in ft. collins i can buy 100 and 104 at the pump at some place, i forgot the name of the road, but its just east of boyd lake. still too far of a drive but when i'm up there i usually get a few gallons.
if i'm ever in that area i'll have to stop buy, but i'm almost never down south.
thanks for the info!
if i'm ever in that area i'll have to stop buy, but i'm almost never down south.
thanks for the info!
